In liquid chromatography, a solution in which a sample has been dissolved is allowed to pass through a stationary phase filled in a column. At this time, for each component in the sample introduced into the column, it takes a different time to pass through the column depending on the interaction with the stationary phase, the affinity for a mobile phase, or the like, and therefore, each component is separated at the time point when the components are discharged from the column. A substance that strongly interacts with a stationary phase, or has weak affinity for a mobile phase stays long in a column and discharged slowly from the column.
In such a liquid chromatography, selection of the solvent species, and selection of the column size are important, and the elution time and the separation degree of a sample are closely related to these conditions. Therefore, if the test results are predicted before actually performing the liquid chromatography, the efficiency of the experiment can be improved.
There is thin-layer chromatography (TLC) that is performed based on the same principle as that in the liquid chromatography. In the thin-layer chromatography, onto a material to be used as a stationary phase in a column, which is a thin layer, a sample is dropped, and then, this thin layer is immersed in an eluent that is to be a mobile layer. Further, by the action of sucking up the sample together with the eluent being sucked up in the thin layer due to capillarity, the mobility Rf of the sample for the eluent can be determined. It is known that there is a correlation between the mobility Rf thus determined by TLC which is performed with an eluent having an arbitrary solvent ratio, and the elution time of liquid chromatography.
The present applicant has filed Patent Document 1 for a control device of liquid chromatography, in which a result of liquid chromatography is predicted in advance based on the result of TLC by utilizing the correlation obtained between the result of TLC and the separation degree of liquid chromatography, and liquid chromatography is efficiently performed by the prediction.
In Patent Document 1, as to the relationship between the mobility Rf and the mixing ratio (B/A) of solvents, approximate processing based on a linear function is performed. From the point of predicting the result of liquid chromatography from the result of TLC by such an approximation, Patent Document 1 is extremely useful for industrial purposes.
In addition, the present inventors further improved Patent Document 1 in Japanese Patent Application No. 2015-152510, and developed a technique with regard to performing the prediction of liquid chromatography based on the relationship between log k′ and log B.
However, depending on a sample, there was a case where in the method described above, the prediction performed based on the result of thin-layer chromatography was inconsistent with the result of the actual liquid chromatography. In such a case, a chromatography method by the methods as in the prior art documents does not function well, and a result as predicted cannot be obtained.
Accordingly, investigation with regard to a prediction method for a result of liquid chromatography based on a result of thin-layer chromatography, which can apply to even such a case, has been required.